Endless belts are used in a number of different abusive environment applications, such as conveyor belts used in various material handling applications such as package handling. Conventional conveyor belts consist of a woven reinforcing fabric embedded inside a flexible matrix of polyvinyl chloride or the like. The reinforcing fabric is woven by interlacing multiple warp yarns with multiple weft yarns. The warp yarns extend in the longitudinal or travel direction of the belt, and the weft yarns are placed at right angles to the warp yarns. The breaking strength of the warp yarns defines the tensile strength of the belt.
Conveyor belts are susceptible to lengthwise tearing parallel to the direction of belt travel and parallel to the direction of the warp yarns if foreign objects originating from the conveyed material wedge or lodge in the conveyor structure and maintain a stationary contacting position relative to the moving belt. For example, such foreign objects may be trapped or pinched at the transfer junction between adjacent conveyors in a material handling system. The tearing susceptibility arises from the inability of the reinforcing fabric inside the belt to resist the force applied by the stationary foreign object. The belt's tear strength is dependent primarily upon the breaking strength of the weft yarns and how those yarns are oriented for resisting the stress applied by the foreign object. The reinforcing fabrics of conventional conveyor belts lack sufficient tear strength to prevent longitudinal tearing due to contact by such stationary foreign objects.
What is needed, therefore, is a reinforcing fabric for a conveyor belt characterized by an increased tear resistance in the direction of travel.